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饲料中可利用氨基酸就是指能被动物消化吸收参与机体蛋白质代谢的氨基酸。以可利用氨基酸配制蛋鸡日粮,就是在测知了饲料原料氨基酸含量及利用率和畜禽氨基酸需要量的基础上,采用电子计算机优选,配制成满足家禽生长、产蛋需要的可利用氨基酸平衡日粮。用此技术配制的日粮更接近家禽实际需要,并可合理利用售价低廉的棉、菜籽饼粕,充分发挥家禽生产性能,从而获得最大的经济效益。 相似文献
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一、可消化氨基酸配方的理论基础蛋白质原料是饲料原料中最贵重的物质之一,蛋白质的开销是饲料成本中最重要的部分。如何节约蛋白资源,利用可消化氨基酸平衡理论进行饲料日粮配方的设计是行之有效的方法。配合饲料中可消化氨基酸的含量及其平衡程度是影响饲料品质和效益的一个重要因素。准确地测定饲料中可消化氨基酸含量及动物可消化氨基酸的需要量是配制可消化氨基酸平衡日粮的技术关键。动物可消化氨基酸的需要量是源于理想蛋白质的概念。所谓理想蛋白质就是能够被特定动物完全 相似文献
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利用可消化氨基酸理想模式配制肉鸡日粮的建议 总被引：1，自引：0，他引：1
目前,世界各国所推荐的肉鸡氨基酸需要量皆以总的氨基酸为基础。然而由于各种饲料中每种氨基酸消化率差异较大,由此所造成的偏差就会使一些氨基酸过剩而另一些氨基酸不足,影响氮沉积和动物的生产性能。利用可消化氨基酸理想模式配制肉鸡日粮可缩小这种偏差,使之更进一步接近动物的需求。 1 饲料中可消化氨基酸的含量 肉鸡对不同饲料中各种氨基酸的利用率有很大差异,用可消化氨基酸比总氨基酸含量更能反应其营养 相似文献
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畜禽饲料氨基酸利用率的影响因素 总被引：9，自引：0，他引：9
近年来，畜禽蛋白营养研究逐渐从日粮总氨基酸含量发展到可利用氨基酸。科学研究和生产实践证明引入氨基酸利用率和以可利用氨基酸含量为基础配制日粮可以：（１）准确地实现营养素间平衡，满足畜禽对氨基酸的真需要，从而最大限度地发挥畜禽生产潜力；（２）降低氨基酸供给量的“保险系数”，节约蛋白饲料和合成氨基酸，降低日粮配方成本；（３）合理利用谷物加工副产品、杂粕、羽毛粉、血粉等非常规蛋白质饲料，减少“人畜争粮”的压力，增加饲养量；（４）降低畜禽排泄物中氮的排泄量，减轻畜牧业对环境的污染。氨基酸利用率是一个受动物… 相似文献
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《饲料工业》2021,(12)
乌克兰产葵花籽粕产量大、供应充足,是补充我国蛋白质饲料原料不足的重要渠道,但对其营养物质含量及氨基酸表观利用率并不太清楚。此次试验测定乌克兰产葵花籽粕中的主要营养物质含量以及其氨基酸表观利用率,以期能为乌克兰产葵花籽粕在配合饲料中的合理利用提供科学依据。试验通过化学分析方法测定各类营养物质含量;利用蛋鸡作为试验动物,测出了该批葵花籽粕中氨基酸的表观利用率。试验结果显示,该批葵花籽粕中粗蛋白质的含量为42.27%,粗纤维的含量为14.81%,钙、磷元素含量分别为0.37%和0.99%;试验所测的15种氨基酸总量高达34.8%,氨基酸的表观利用率除甘氨酸和蛋氨酸以外,整体都达到了80%以上。根据试验结果得出结论:乌克兰产葵花籽粕中粗蛋白质和氨基酸含量较高,氨基酸表观利用率整体上与菜籽粕相当,是较优异的植物性蛋白质饲料,但部分氨基酸不平衡现象也比较明显。 相似文献
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以可消化氨基酸为基础配制产蛋鸡日粮试验河南省邓州市饲料公司王团先由于饲料原料的种类、来源、加工方法等不同，它们的氨基酸消化率（即被动物吸收利用的有效率）也存在很大差异。因此，以氨基酸总量来设计日粮配方是不够准确可靠的，而以可消化氨基酸为基础配制日粮则... 相似文献
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以可消化氨基酸为基础配制产蛋鸡日粮试验河南省邓州市饲料公司王团先由于饲料原料的种类、来源、加工方法等不同，它们的氨基酸消化率（即被动物吸收利用的有效率）也存在很大差异。因此，以氨基酸总量来设计日粮配方是不够准确可靠的。而以可消化氨基酸为基础配制日粮则... 相似文献
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前言“可利用率”(availability)这一概念现已被动物营养界普遍接受,并广泛应用于能量代谢之中。虽然现代离子交换色谱技术已能精确测出饲料中总氨基酸的含量,但由根据总氨基酸配制日粮向根据可利用氨基酸配制日粮的转变却进展缓慢。现在,确定可利用氨基酸的方法很多,有体内法和体外法两种。主要根据准确、灵敏和便于操作这三条原则确定。如果要求实用性,则必须能够测定饲料工业中使用的各种类型的饲料,还要考虑饲料或日粮中其他组分影响氨基酸可利用率的可能性。只有同时根据混合日粮总氨基酸含量和可利用氨基酸含量,全面评价日粮的相对 相似文献
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测定鸡饲料氨基酸代谢率是进行可利用氨基酸营养研究的一项基础性工作。研究证明 ,依据饲料中可消化氨基酸量配制的日粮 ,可维持家禽的生产性能 ,依据总氨基酸量配制的日粮却无此效果 ,以可消化氨基酸为基础配制的日粮 ,可更有效地利用氨基酸利用率较低的蛋白质饲料。由于鸡氨基酸代谢率测定方法的非标准化以及存在的某些缺陷 ,在营养研究和饲养实践中广泛应用可利用氨基酸概念仍存在不少困难。本研究基于加拿大 I.R.Sibbald提出的快速法以及当前争议最大的去盲肠法 ,在高原地区不同季节采用不同类型鸡以及不同方法测定了氨基酸代谢率 ,一… 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献